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41.
A linear mathematical model of the electromyogram (e.m.g.) has been developed for the biceps muscle. The number of motor units (and therefore muscle fibres) contributing to the resultant e.m.g. at any stage of movement has been found from the force analysis of elbow flexion. The depths of various motor units and the phase difference between the recruitment of any two motor units have been formulated using a spiral spread of recruitment sequence. The attenuation of individual motor-unit action potentials due to varying depths has been taken into consideration, and due regard has been taken of the length-tension diagram of a muscle while performing the force analysis. Attention has been focused on the flexion of the elbow joint, in which a method of finding the individual contribution of the biceps and brachialis muscles has been developed and applied. The results predicted by the model have been verified by experiments. The model can also be extended to the e.m.g. of other fast skeletal muscles. The conditions and limitations for such generalisations have been stated and discussed. 相似文献
42.
A large area and highly sensitive thermoluminescent (TL) sheet film was used for two-dimensional dose distribution measurements at millimetre distances from a 103Pd interstitial brachytherapy source. The TL film is made of Teflon homogeneously mixed with small particles of thermoluminescent material (BaSO4: Eu doped). This TL sheet (5 cm x 5 cm) was used to determine the relative dosimetric characteristics (i.e., radial dose function, 2D and 1D anisotropy functions, as defined by the updated AAPM Task Group No 43 report) of the model 200 103Pd source that emits low energy photons (21 keV). The two-dimensional dosimetry data were obtained for distances from the source surface to 15 mm. The radial dose function measured with the TL sheet is in reasonable agreement within 11% with the values recommended in the updated AAPM TG-43 report. All the measured 2D dose distributions showed limited symmetry about the source axes. The differences between the 1D anisotropy function values measured with the TL sheet and the data recommended in the updated AAPM TG-43 report were 10% at 5 mm and 7.5% at 10 mm, respectively, for the model 200 103Pd seed. Our experiments have demonstrated that it is feasible to use the TL sheet as a dosimeter in the determination of the dosimetric characteristics in the immediate vicinity of interstitial brachytherapy sources emitting low energy photons. 相似文献
43.
To determine how women in pregnancy would like to be addressed and to ascertain their preferred choice of title during pregnancy. A questionnaire was administered to 925 antenatal women. Midwifery and medical staff (183) were invited to respond to a similar questionnaire. The response rate was 71.2% from the survey of pregnant women. The vast majority (82.1%) preferred to be addressed by their first name. Women were in favour of being called 'patient' (32.8%) as their first choice. The staff survey yielded a response rate of 77%. The majority (81.8%) of health professionals preferred to address women by their first name. 'Mother' (28.7%) was the most popular first choice. We conclude that women in pregnancy do have a preference on how they would like to be addressed and this is predominantly by first name. Health professionals also prefer to call pregnant women by their first name. The term 'patient' was the most popular first choice of title of women in pregnancy but the term 'mother' was the preferred choice of the health professionals. Medical staff were more likely to choose 'patient' than midwives. 相似文献
44.
Nath D Hartnell A Happerfield L Miles DW Burchell J Taylor-Papadimitriou J Crocker PR 《Immunology》1999,98(2):213-219
In many carcinomas, infiltrating macrophages are commonly found closely associated with tumour cells but little is known concerning the nature or significance of adhesion molecules involved in these cellular interactions. Here we demonstrate in primary human breast cancers that sialoadhesin (Sn), a macrophage-restricted adhesion molecule, is frequently expressed on infiltrating cells that often make close contact with breast carcinoma cells. To determine whether Sn could act as a specific receptor for ligands on breast cancer cell lines, binding assays were performed with a recombinant form of the protein fused to the Fc portion of human immunoglobulin G1 (IgG1) (Sn-Fc). Sn-Fc was found to bind specifically and in a sialic acid-dependent manner to the breast cancer cell lines MCF-7, T47.D and BT-20 both in solid- and solution-phase binding assays. To investigate the nature of the sialoglycoproteins recognized by Sn on breast cancer cells, MCF-7 cells were labelled with [6-3H]glucosamine. Following precipitation with Sn-Fc, a major band of approximately 240000 MW was revealed, which was shown in reprecipitation and Western blotting experiments to be the epithelial mucin, MUC1. 相似文献
45.
By applying a transverse magnetic field to a dosimetry phantom, an incident high-energy electron beam is made to follow a spiral path in the course of slowing down. Certain levels, determined by the electron energy and the magnetic field strength, will be traversed several times by the same electrons. The net result of this process is an enhancement of the depth dose in relation to the entrance dose, and a more sharply defined depth of penetration. Experiments with 50- and 55-MeV electrons traversing a 20.5-kG field are shown to support the predictions of a detailed Monte Carlo calculation. 相似文献
46.
Bengal Soumyaneel Das Rabindra Nath Roy Dilip Kumar Das Amitava Chakraborty Raston Mondal 《Ethiopian journal of health sciences》2021,31(2):275
BackgroundInjuries are a focus of public health practice because they pose a serious health threat and are preventable. Currently, injury accounts for 14% of all Disability Adjusted Life Years (DALYs) losses for the world''s entire population. In India, unintentional injuries within the home environment have not so far been recognized to the same extent as traffic and work-related injuries among all age groups. With this background, a community based epidemiological study was conducted with the aim to find out the prevalence and epidemiology of unintentional injuries.MethodsA cross-sectional study was conducted during July 2018 - June 2019 in Bhatar block of Purba Bardhaman District. Cluster random sampling was applied to select required sample of 555 individuals from 24 villages. The study tools used were a predesigned and pretested schedule developed by the researchers with the help of Guidelines for conducting community surveys on injuries by World Health Organization (WHO) and a checklist for assessing household level injury hazard. The study had approval from Institutional Ethics Committee. Chi square test and multivariable logistic regression were performed using SPSS V16.ResultsPrevalence of unintentional injury was 8.8 % in the preceding three months. Multivariable logistic regression revealed that those who were below 18 years of age, severely vulnerable to unintentional injuries and belonged to nuclear families had significantly higher odds of developing unintentional injuries at home.ConclusionUnintentional injury is prevalent in West Bengal. Dissemination of injury prevention information with special focus on household modification is an effective strategy to prevent unintentional injuries. 相似文献
47.
Mayukh Guha Hitesh Lal Tankeswar Boruah Sapan Kumar Atul Sareen Mohit Kumar Patralekh Ramesh Kumar Geetika Khanna 《Indian Journal of Orthopaedics》2021,55(4):1028
Background/Purpose of the StudyC-arm-guided biopsy is a safe and effective technique for evaluating TB spine and is useful in planning therapy. The purpose of this study was to find a correlation between clinically and radiologically suspected TB spine and C-arm image-guided biopsy-proven cases and to study the complications encountered.MethodsAfter evaluating the clinical, laboratory, X-ray and MRI findings, 92 patients with provisionally diagnosed tubercular spine were subjected to C-arm image-guided biopsy.ResultsAmong our 92 cases, histopathology was positive in 55 cases (59.78%). Out of these 55 histologically positive cases, CBNAAT was positive in 42 cases and negative in the rest 13 cases. Overall, among the 92 cases, CBNAAT was positive in 51(55.43%) of cases, and out of these, histopathology turned out to be positive in 42 of cases. Out of 41 cases with negative CBNAAT, histopathology was suggestive of tuberculosis in 13. The strength of agreement between CBNAAT and histopathology was statistically significant (p < 0.0001; kappa = 0.511). No complication such as bleeding, nerve/cord injury, infection, injury to aorta or pneumothorax was encountered during and after the C-arm biopsy in any case.ConclusionC-arm image-guided biopsy is reasonably accurate and should be used as a tool for diagnosis of TB spine. We recommend histopathological examination as a key component for the diagnosis of TB spine, as it is precise and consumes relatively shorter time. CBNAAT is more rapid but is not a substitute for histopathology for spine TB diagnosis. 相似文献
48.
Nath C Patnaik GK Saxena RC Gupta MB 《Indian journal of physiology and pharmacology》1997,41(1):42-46
Effect of diphenhydramine was investigated on withdrawal signs in lorazepam dependent rats. Physical dependence was produced by giving lorazepam admixed with the food in the following dose schedule: 10 x 4, 20 x 4, 40 x 4, 80 x 4 and 120 x 7 (mg/kg, daily x days). The parameters observed during the periods of administration of lorazepam and after its withdrawal were spontaneous locomotor activity (SLA), body temperature, reaction time to pain, foot shock aggression (FSA) and audiogenic seizures. Diphenhydramine was administered orally in the dose schedules of once daily (10, 20 and 40 mg/kg) and twice daily (5, 10 and 20 mg/kg) in separate groups during the withdrawal period. The withdrawal signs observed in control group (without diphenhydramine) were hyperkinesia, hyperthermia, hyperaggression and audiogenic seizures. Hyperkinesia and hyperthermia were blocked in all the groups of diphenhydramine-treated rats. FSA was inhibited only by diphenhydramine (10 and 20 mg/kg) given twice daily. Audiogenic seizures were completely blocked by once daily (20 and 40 mg/kg) as well as twice daily (20 mg/kg) doses of diphenhydramine. It may be concluded that diphenhydramine exerts a protective effects on benzodiazepine withdrawal syndrome. 相似文献
49.
50.
Isatin and its derivatives have been reacted with 4-(4'-chlorophenyl)-6-(4"-methyl phenyl)-2-aminopyrimidine to form Schiff bases and the N-Mannich bases of these compounds were synthesized by reacting them with formaldehyde and several secondary amines. Investigation of antimicrobial activity of the compounds was made by the agar dilution method against 28 pathogenic bacteria, eight pathogenic fungi and anti-HIV activity against replication of HIV-1 (III B) in MT-4 cells. The compounds are significantly active against bacteria and fungi. 相似文献